Never say never, the only reason why tag is not on the roadmap yet is because I couldnt find a way to add it without loading all of the tags into memory.
Yes, it's stored as a binary object instead of markdown because of that! The changes I made to migrate the whole backend from ReDB to Sqlite is still very new, thanks for reminding me to mention it in the docs!
Maybe ERPNext could do it. It has many modules, including CRM! https://erpnext.com/